In a manufacturing process of a semiconductor device, a probe device is used to perform an electrical test of a semiconductor device formed on a semiconductor wafer. In the probe device, a semiconductor wafer is mounted on a mounting table (chuck top) and electrical conduction is obtained by driving the mounting table to bring probes into contact with electrodes of the semiconductor device of the semiconductor wafer. The test of the semiconductor device is performed by applying a predetermined test signal from a measuring device (tester) to the semiconductor device through the probe and detecting an output signal from the semiconductor device.
In a probe device for performing an electrical test of a semiconductor device having an electrode at the backside of the semiconductor wafer, e.g., a power device having a collector electrode formed at the backside of the semiconductor wafer, a conductive film electrode made of a conductive metal such as gold is formed as a mounting table electrode at a mounting surface of a mounting table (chuck top) and the conductive film electrode is made contact with the electrode formed at the backside of the semiconductor wafer, thereby obtaining electrical conduction. The power device has a high withstand voltage and a high current compared to a general semiconductor device and may have a high speed and a high frequency depending on purpose. An insulated-gate bipolar transistor (IGBT), a diode, a power transistor, a power MOSFET, a thyristor and the like may be used as the power device. The quality of the power device is determined by measuring its electrical characteristic (static characteristic and dynamic characteristic).
Further, in the probe device for performing an electrical test of the power device and the like, if the conductive film electrode and the tester are electrically connected to each other by a cable or the like, the cable becomes longer due to a driving type of the mounting table and this leads to an increase of resistance or inductance of the cable. For this reason, there has been known a probe device having a configuration that a metallic connection conductor electrically connected to the conductive film electrode is provided at a side surface of the mounting table and the connection conductor is made contact with a metallic electrode plate provided above the mounting table to obtain electrical conduction (see, e.g., Patent Document 1).
Patent Document 1: Japanese Patent Application Publication No. 2012-58225.
However, in the probe device having the above configuration, since electrical conduction is obtained by making the metallic connection conductor contact with the metallic electrode plate, metal pieces and the like are generated by the contact and a contact resistance between the connection conductor and the electrode plate gradually increases while the test is performed repeatedly. Accordingly, it may be difficult to perform a test having a high precision.